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author | marha <marha@users.sourceforge.net> | 2009-10-08 13:15:52 +0000 |
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committer | marha <marha@users.sourceforge.net> | 2009-10-08 13:15:52 +0000 |
commit | a0c4815433ccd57322f4f7703ca35e9ccfa59250 (patch) | |
tree | f5213802ec12adb86ec3136001c1c29fe5343700 /mesalib/src/glu/sgi/libnurbs/internals/tobezier.cc | |
parent | c73dc01b6de45612b24dc2dd34fba24d81ebf46c (diff) | |
download | vcxsrv-a0c4815433ccd57322f4f7703ca35e9ccfa59250.tar.gz vcxsrv-a0c4815433ccd57322f4f7703ca35e9ccfa59250.tar.bz2 vcxsrv-a0c4815433ccd57322f4f7703ca35e9ccfa59250.zip |
Added MesaLib-7.6
Diffstat (limited to 'mesalib/src/glu/sgi/libnurbs/internals/tobezier.cc')
-rw-r--r-- | mesalib/src/glu/sgi/libnurbs/internals/tobezier.cc | 687 |
1 files changed, 687 insertions, 0 deletions
diff --git a/mesalib/src/glu/sgi/libnurbs/internals/tobezier.cc b/mesalib/src/glu/sgi/libnurbs/internals/tobezier.cc new file mode 100644 index 000000000..531f26bc7 --- /dev/null +++ b/mesalib/src/glu/sgi/libnurbs/internals/tobezier.cc @@ -0,0 +1,687 @@ +/* +** License Applicability. Except to the extent portions of this file are +** made subject to an alternative license as permitted in the SGI Free +** Software License B, Version 1.1 (the "License"), the contents of this +** file are subject only to the provisions of the License. You may not use +** this file except in compliance with the License. You may obtain a copy +** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600 +** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at: +** +** http://oss.sgi.com/projects/FreeB +** +** Note that, as provided in the License, the Software is distributed on an +** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS +** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND +** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A +** PARTICULAR PURPOSE, AND NON-INFRINGEMENT. +** +** Original Code. The Original Code is: OpenGL Sample Implementation, +** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics, +** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc. +** Copyright in any portions created by third parties is as indicated +** elsewhere herein. All Rights Reserved. +** +** Additional Notice Provisions: The application programming interfaces +** established by SGI in conjunction with the Original Code are The +** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released +** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version +** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X +** Window System(R) (Version 1.3), released October 19, 1998. This software +** was created using the OpenGL(R) version 1.2.1 Sample Implementation +** published by SGI, but has not been independently verified as being +** compliant with the OpenGL(R) version 1.2.1 Specification. +*/ + +/* + * tobezier.c++ + * + */ + +#include "glimports.h" +#include "myassert.h" +#include "mystdio.h" +#include "mystring.h" +#include "quilt.h" +#include "knotvector.h" + +/* local type definitions */ +struct Breakpt { /* breakpoints */ + Knot value; /* value */ + int multi; /* multiplicity */ + int def; /* deficit */ +}; + +struct Knotspec { /* knotvector format */ + long order; /* order of spline */ + Knot_ptr inkbegin; /* input knot sequence */ + Knot_ptr inkend; /* location after last knot */ + Knot_ptr outkbegin; /* in-process knot subsequence */ + Knot_ptr outkend; /* location after last knot */ + Knot_ptr kleft; /* */ + Knot_ptr kright; /* */ + Knot_ptr kfirst; /* */ + Knot_ptr klast; /* */ + Knot_ptr sbegin; /* conversion factor values */ + Breakpt * bbegin; /* in-process breakpoints */ + Breakpt * bend; /* last breakpoint */ + int ncoords; /* coordinates per control point */ + int prestride; /* stride between input points */ + int poststride; /* stride between output points */ + int preoffset; /* scaled point offset */ + int postoffset; /* scaled point offset */ + int prewidth; /* width of dimension */ + int postwidth; /* width of dimension */ + int istransformed; /* was dimension transformed */ + Knotspec * next; /* next knotspec */ + Knotspec * kspectotrans; /* knotspec in transformation direction */ + + Knotspec( void ); + ~Knotspec( void ); + void factors( void ); + void insert( REAL * ); + void preselect(); + void select( void ); + void copy( INREAL *, REAL * ); + void breakpoints( void ); + void knots( void ); + void transform( REAL * ); + void showpts( REAL * ); + + void pt_io_copy( REAL *, INREAL * ); + void pt_oo_copy( REAL *, REAL * ); + void pt_oo_sum( REAL*, REAL*, REAL*, Knot, Knot ); +}; + +struct Splinespec { /* a non-uniform tensor element */ + Splinespec( int ); + ~Splinespec(void); + Knotspec *kspec; /* format of each param. dir. */ + int dim; /* domain dimension */ + REAL * outcpts; /* Bezier control points */ + + void kspecinit( Knotvector & ); + void kspecinit( Knotvector &, Knotvector & ); + void select( void ); + void layout( long ); + void setupquilt( Quilt_ptr ); + void copy( INREAL * ); + void transform( void ); +}; + +/*----------------------------------------------------------------------------- + * Quilt::toBezier - convert from NURBS to rational Bezier + *----------------------------------------------------------------------------- + */ + +void +Quilt::toBezier( + Knotvector& knotvector, /* a knot vector */ + INREAL *ctlpts, /* input contol points */ + long ncoords ) /* number of coordinates per control point */ +{ + Splinespec spline( 1 ); + spline.kspecinit( knotvector ); + spline.select(); + spline.layout( ncoords ); + spline.setupquilt( this ); + spline.copy( ctlpts ); + spline.transform(); +} + +void +Quilt::toBezier( + Knotvector& sknotvector, /* a knot vector */ + Knotvector& tknotvector, /* a knot vector */ + INREAL *ctlpts, /* input contol points */ + long ncoords ) /* number of coordinates per control point */ +{ + Splinespec spline( 2 ); + spline.kspecinit( sknotvector, tknotvector ); + spline.select(); + spline.layout( ncoords ); + spline.setupquilt( this ); + spline.copy( ctlpts ); + spline.transform(); +} +Splinespec::Splinespec( int dimen ) +{ + dim = dimen; +} + +Splinespec::~Splinespec( void ) +{ + /* Note: do NOT delete 'outcpts' here since its address (not contents) + * is copied in 'cpts' in this file in function Splinespec::setupquilt(). + * This block of memory will eventually be deleted in file quilt.c++ in + * function Quilt::deleteMe() through 'cpts' so do NOT delete it here! + */ + Knotspec *ktrav= kspec; //start at beginning of list + while (ktrav != 0) { //any items to delete? + Knotspec *deleteThis= ktrav; //remember to delete this + ktrav= ktrav->next; //go to next item if any + delete deleteThis; //delete it + } +} /* ~Splinespec() */ + +/*----------------------------------------------------------------------------- + * Splinespec::kspecinit - initialize Splinespec structure + * + * Client: Quilt::toBezier + *----------------------------------------------------------------------------- + */ + +void +Splinespec::kspecinit( Knotvector& knotvector ) +{ + kspec = new Knotspec; + kspec->inkbegin = knotvector.knotlist; + kspec->inkend = knotvector.knotlist + knotvector.knotcount; + kspec->prestride = (int) knotvector.stride; + kspec->order = knotvector.order; + kspec->next = NULL; +} + +void +Splinespec::kspecinit( Knotvector& sknotvector, Knotvector& tknotvector ) +{ + kspec = new Knotspec; + Knotspec *tkspec = new Knotspec; + + kspec->inkbegin = sknotvector.knotlist; + kspec->inkend = sknotvector.knotlist + sknotvector.knotcount; + kspec->prestride = (int) sknotvector.stride; + kspec->order = sknotvector.order; + kspec->next = tkspec; + + tkspec->inkbegin = tknotvector.knotlist; + tkspec->inkend = tknotvector.knotlist + tknotvector.knotcount; + tkspec->prestride = (int) tknotvector.stride; + tkspec->order = tknotvector.order; + tkspec->next = NULL; +} + + +/*----------------------------------------------------------------------------- + * Splinespec::select - select the subsegments to copy + * + * Client: gl_quilt_to_bezier + *----------------------------------------------------------------------------- + */ + +void +Splinespec::select( ) +{ + for( Knotspec *knotspec = kspec; knotspec; knotspec = knotspec->next ) { + knotspec->preselect(); + knotspec->select(); + } +} + +/*----------------------------------------------------------------------------- + * Splinespec::layout - + * + * Client: gl_quilt_to_bezier + *----------------------------------------------------------------------------- + */ + +void +Splinespec::layout( long ncoords ) +{ + + long stride = ncoords; + for( Knotspec *knotspec = kspec; knotspec; knotspec=knotspec->next ) { + knotspec->poststride = (int) stride; + stride *= ((knotspec->bend-knotspec->bbegin)*knotspec->order + knotspec->postoffset); + knotspec->preoffset *= knotspec->prestride; + knotspec->prewidth *= knotspec->poststride; + knotspec->postwidth *= knotspec->poststride; + knotspec->postoffset *= knotspec->poststride; + knotspec->ncoords = (int) ncoords; + } + outcpts = new REAL[stride]; + assert( outcpts != 0 ); +} + +/*----------------------------------------------------------------------------- + * Splinespec::copy - copy the control points of current subobject + * + * Client: gl_quilt_to_bezier + *----------------------------------------------------------------------------- + */ + +void +Splinespec::copy( INREAL *incpts ) +{ + kspec->copy( incpts, outcpts ); +} + +/*----------------------------------------------------------------------------- + * Splinespec::setupquilt - assign all quilt variables from knotspec + * + * Client: gl_quilt_to_bezier + *----------------------------------------------------------------------------- + */ + +void +Splinespec::setupquilt( Quilt_ptr quilt ) +{ + Quiltspec_ptr qspec = quilt->qspec; + quilt->eqspec = qspec + dim; + for( Knotspec *knotspec = kspec; knotspec; knotspec=knotspec->next, qspec++ ) { + qspec->stride = knotspec->poststride; + qspec->width = knotspec->bend - knotspec->bbegin; + qspec->order = (int) knotspec->order; + qspec->offset = knotspec->postoffset; + qspec->index = 0; + qspec->bdry[0] = (knotspec->kleft == knotspec->kfirst) ? 1 : 0; + qspec->bdry[1] = (knotspec->kright == knotspec->klast) ? 1 : 0; + qspec->breakpoints = new Knot[qspec->width+1]; + Knot_ptr k = qspec->breakpoints; + for( Breakpt *bk = knotspec->bbegin; bk <= knotspec->bend; bk++ ) + *(k++) = bk->value; + } + quilt->cpts = outcpts; + quilt->next = 0; +} + +/*----------------------------------------------------------------------------- + * Splinespec::transform - convert a spline to Bezier format + * + * Client: gl_quilt_to_bezier + *----------------------------------------------------------------------------- + */ + +void +Splinespec::transform( void ) +{ + Knotspec *knotspec; + for( knotspec = kspec; knotspec; knotspec=knotspec->next ) + knotspec->istransformed = 0; + + for( knotspec = kspec; knotspec; knotspec=knotspec->next ) { + for( Knotspec *kspec2 = kspec; kspec2; kspec2=kspec2->next ) + kspec2->kspectotrans = knotspec; + kspec->transform( outcpts ); + knotspec->istransformed = 1; + } +} + + +/*----------------------------------------------------------------------------- + * Knotspec::Knotspec - constuct a knot spec + *----------------------------------------------------------------------------- + */ + +Knotspec::Knotspec( void ) +{ + bbegin = 0; + sbegin = 0; + outkbegin = 0; +} + +/*----------------------------------------------------------------------------- + * Knotspec::copy - copy the control points along minor direction + * + * Client: Splinespec::copy + *----------------------------------------------------------------------------- + */ + +void +Knotspec::copy( INREAL *inpt, REAL *outpt ) +{ + inpt = (INREAL *) (((char *) inpt) + preoffset); + + if( next ) { + for( REAL *lpt=outpt+prewidth; outpt != lpt; outpt += poststride ) { + next->copy( inpt, outpt ); + inpt = (INREAL *) (((char *) inpt) + prestride); + } + } else { + for( REAL *lpt=outpt+prewidth; outpt != lpt; outpt += poststride ) { + pt_io_copy( outpt, inpt ); + inpt = (INREAL *) (((char *) inpt) + prestride); + } + } +} + +/*----------------------------------------------------------------------------- + * Knotspec::showpts - print out points before transformation + * + * Client: Knotspec::select + *----------------------------------------------------------------------------- + */ +void +Knotspec::showpts( REAL *outpt ) +{ + if( next ) { + for( REAL *lpt=outpt+prewidth; outpt != lpt; outpt += poststride ) + next->showpts( outpt ); + } else { + for( REAL *lpt=outpt+prewidth; outpt != lpt; outpt += poststride ) + _glu_dprintf( "show %g %g %g\n", outpt[0], outpt[1], outpt[2] ); + } +} + +/*----------------------------------------------------------------------------- + * Knotspec::factors - precompute scale factors + * - overwrites knot vector, actual new knot vector is NOT produced + * + * Client: Knotspec::select + *----------------------------------------------------------------------------- + */ + +void +Knotspec::factors( void ) +{ + Knot *mid = (outkend - 1) - order + bend->multi; + Knot_ptr fptr = sbegin; + + for( Breakpt *bpt = bend; bpt >= bbegin; bpt-- ) { + mid -= bpt->multi; // last knot less than knot to insert + int def = bpt->def - 1; // number of knots to insert + if( def <= 0 ) continue; + Knot kv = bpt->value; // knot to insert + + Knot *kf = (mid-def) + (order-1); + for( Knot *kl = kf + def; kl != kf; kl-- ) { + Knot *kh, *kt; + for( kt=kl, kh=mid; kt != kf; kh--, kt-- ) + *(fptr++) = (kv - *kh) / (*kt - *kh); + *kl = kv; + } + } +} + +/*----------------------------------------------------------------------------- + * Knotspec::insert - convert subobject in direction of kspec into Bezier + * + * Client: Knotspec::transform + *----------------------------------------------------------------------------- + */ + +void +Knotspec::insert( REAL *p ) +{ + Knot_ptr fptr = sbegin; + REAL *srcpt = p + prewidth - poststride; + REAL *dstpt = p + postwidth + postoffset - poststride; + Breakpt *bpt = bend; + + for( REAL *pend = srcpt - poststride*bpt->def; srcpt != pend; pend +=poststride ) { + REAL *p1 = srcpt; + for( REAL *p2 = srcpt-poststride; p2 != pend; p1 = p2, p2 -= poststride ) { + pt_oo_sum( p1, p1, p2, *fptr, 1.0-*fptr ); + fptr++; + } + } + + for( --bpt; bpt >= bbegin; bpt-- ) { + + for( int multi = bpt->multi; multi > 0; multi-- ) { + pt_oo_copy( dstpt, srcpt ); + dstpt -= poststride; + srcpt -= poststride; + } + + for( REAL *pend = srcpt - poststride*bpt->def; srcpt != pend; pend +=poststride, dstpt-=poststride ) { + pt_oo_copy( dstpt, srcpt ); + REAL *p1 = srcpt; + + for( REAL *p2 = srcpt-poststride; p2 != pend; p1=p2, p2 -= poststride ) { + pt_oo_sum( p1, p1, p2, *fptr, 1.0-*fptr ); + fptr++; + } + } + } +} + +/*----------------------------------------------------------------------------- + * Knotspec::preselect - initialize kspec for processing + * + * Client: Splinespec::select + *----------------------------------------------------------------------------- + */ + +void +Knotspec::preselect( void ) +{ + Knot kval; + + /* position klast after last knot of "last" breakpoint */ + for( klast = inkend - order, kval = *klast; klast != inkend; klast++ ) + if( ! identical( *klast, kval ) ) break; + + /* position kfirst after last knot of "first" breakpoint */ + for( kfirst = inkbegin+order-1, kval= *kfirst; kfirst != inkend; kfirst++ ) + if( ! identical( *kfirst, kval ) ) break; + + /* compute multiplicity of first breakpoint */ + Knot_ptr k; + for( k = kfirst - 1; k >= inkbegin; k-- ) + if( ! identical( kval, *k ) ) break; + k++; + + /* allocate space for breakpoints - + use worst case estimate on number of breakpoints */ + + bbegin = new Breakpt[(klast - kfirst)+1]; + /* record multiplicity and value of first breakpoint */ + bbegin->multi = kfirst - k; + bbegin->value = kval; + bend = bbegin; + + kleft = kright = kfirst; +} + + +/*----------------------------------------------------------------------------- + * Knotspec::select - Knotspec::select segments and precompute scale factors + * + * Client: Splinespec::select + *----------------------------------------------------------------------------- + */ + +void +Knotspec::select( void ) +{ + breakpoints(); + knots(); + factors(); + + preoffset = kleft - (inkbegin + order); + postwidth = (int)((bend - bbegin) * order); + prewidth = (int)((outkend - outkbegin) - order); + postoffset = (bbegin->def > 1) ? (bbegin->def-1) : 0; +} + +/*----------------------------------------------------------------------------- + * Knotspec::breakpoints - compute breakpoints for knotspec + * + * Client: Knotspec::select + *----------------------------------------------------------------------------- + */ + +void +Knotspec::breakpoints( void ) +{ + Breakpt *ubpt = bbegin; + Breakpt *ubend = bend; + long nfactors = 0; + + ubpt->value = ubend->value; + ubpt->multi = ubend->multi; + + kleft = kright; + + for( ; kright != klast; kright++ ) { + if ( identical(*kright,ubpt->value) ) { + (ubpt->multi)++; + } else { + ubpt->def = (int) (order - ubpt->multi); + nfactors += (ubpt->def * (ubpt->def - 1)) / 2; + (++ubpt)->value = *kright; + ubpt->multi = 1; + } + } + ubpt->def = (int) (order - ubpt->multi); + nfactors += (ubpt->def * (ubpt->def - 1)) / 2; + + bend = ubpt; + + if( nfactors ) { + sbegin = new Knot[nfactors]; + } else { + sbegin = NULL; + } +} + + +/*----------------------------------------------------------------------------- + * Knotspec::knots - copy relevant subsequence of knots into temporary area + * + * Client: Knotspec::select + *----------------------------------------------------------------------------- + */ + +void +Knotspec::knots( void ) +{ + Knot_ptr inkpt = kleft - order; + Knot_ptr inkend = kright + bend->def; + + /* allocate space for knots and factors */ + outkbegin = new Knot[inkend-inkpt]; + Knot_ptr outkpt; + for( outkpt = outkbegin; inkpt != inkend; inkpt++, outkpt++ ) + *outkpt = *inkpt; + + outkend = outkpt; +} + + +/*----------------------------------------------------------------------------- + * Knotspec::transform - convert a spline along a given direction + * + * Client: Splienspec::transform + *----------------------------------------------------------------------------- + */ + +void +Knotspec::transform( REAL *p ) +{ + if( next ) { + if( this == kspectotrans ) { + next->transform( p ); + } else { + if( istransformed ) { + p += postoffset; + for( REAL *pend = p + postwidth; p != pend; p += poststride ) + next->transform( p ); + } else { + REAL *pend = p + prewidth; + for( ; p != pend; p += poststride ) + next->transform( p ); + } + } + } else { + if( this == kspectotrans ) { + insert( p ); + } else { + if( istransformed ) { + p += postoffset; + for( REAL *pend = p + postwidth; p != pend; p += poststride ) + kspectotrans->insert( p ); + } else { + REAL *pend = p + prewidth; + for( ; p != pend; p += poststride ) + kspectotrans->insert( p ); + } + } + } +} + +/*----------------------------------------------------------------------------- + * Knotspec::~Knotspec - free space alocated for knotspec + *----------------------------------------------------------------------------- + */ + +Knotspec::~Knotspec( void ) +{ + if( bbegin ) delete[] bbegin; + if( sbegin ) delete[] sbegin; + if( outkbegin ) delete[] outkbegin; +} + + +/*----------------------------------------------------------------------------- + * pt_io_copy - make internal copy of input cntrl pt. of x coords + *----------------------------------------------------------------------------- + */ + +void +Knotspec::pt_io_copy( REAL *topt, INREAL *frompt ) +{ + switch( ncoords ) { + case 4: + topt[3] = (REAL) frompt[3]; + case 3: + topt[2] = (REAL) frompt[2]; + case 2: + topt[1] = (REAL) frompt[1]; + case 1: + topt[0] = (REAL) frompt[0]; + break; + default: { + for( int i = 0; i < ncoords; i++ ) + *topt++ = (REAL) *frompt++; + } + } +} + +/*----------------------------------------------------------------------------- + * pt_oo_copy - make internal copy of internal cntrl pt. of x coords + *----------------------------------------------------------------------------- + */ + +void +Knotspec::pt_oo_copy( REAL *topt, REAL *frompt ) +{ + switch( ncoords ) { + case 4: + topt[3] = frompt[3]; + case 3: + topt[2] = frompt[2]; + case 2: + topt[1] = frompt[1]; + case 1: + topt[0] = frompt[0]; + break; + default: + memcpy( topt, frompt, ncoords * sizeof( REAL ) ); + } +} + +/*----------------------------------------------------------------------------- + * pt_oo_sum - compute affine combination of internal cntrl pts + *----------------------------------------------------------------------------- + */ + +void +Knotspec::pt_oo_sum( REAL *x, REAL *y, REAL *z, Knot a, Knot b ) +{ + switch( ncoords ) { + case 4: + x[3] = a * y[3] + b * z[3]; + case 3: + x[2] = a * y[2] + b * z[2]; + case 2: + x[1] = a * y[1] + b * z[1]; + case 1: + x[0] = a * y[0] + b * z[0]; + break; + default: { + for( int i = 0; i < ncoords; i++ ) + *x++ = a * *y++ + b * *z++; + } + } +} |